What I do
The most common way you hear endodontists explain what they do to other people is that “we save teeth”. I see it a bit differently. In my view, I remove the microbes inside teeth and the patient’s dentist is the hero in “saving” the tooth.
The sad truth about dentistry is that nothing we do can last a lifetime. There are inherent limitations in current dental practice, the materials used do not allow a perfect seal. Margins of restorative materials will eventually leak and the microbes will slowly crawl in between these spaces and cause a reinfection of the root canal spaces.
Removing infection inside the tooth
Endodontic (root canal) treatment aims to disrupt the biofilm located inside the root canal walls by using mechanical instruments and disinfection solutions. Once there is sufficient reduction of the microbial load, the body is then able to heal. These spaces are then filled to slow down the ingress of microbes. It takes about 10-15 years before a reinfection occurs i.e. reinfection of the root canal spaces.
So yes, a root canal treatment is not forever.
Once the root canal treatment is completed, we can observe two things. The first is that the tooth is now hollowed out and there is a hole on the crown. From this, we can say that the walls are thinner and the tooth has a higher risk of fracture. To overcome this problem, the patient’s dentist will usually recommend a full cuspal coverage restoration like a crown, to splint the tooth. Besides providing structural support to the tooth, the restorations also provide an additional seal to prevent the ingress of microbes. The success of a root canal treatment is only as good as the restoration placed after completion of root canal treatment. This is the “coronal seal”, which is done by the patient’s dentist.
Relieving toothaches
Sometimes, decay can progress towards the pulp, and spew toxins that cause the pulp to be inflamed. This is the classical toothache that people often experience. They will say they cannot sleep, the pain is throbbing in nature, and the tooth is extremely sensitive to touch. At this point, it is unlikely that the bacteria managed to infect the root canal spaces, thus the insides of the tooth is most probably sterile. Root canal treatment for cases like this aims to remove the connection to the brain so the pain is no longer felt.